Annealing box



June 17, 1930.

H. WILLIAMS ET AL ANNEALING BOX Filed Feb. 1o, 1928 ----.IFL- .F----T-LTi --.#55 --.NMF-Izsizllb PAT'N'r ier-aceN HARVEY WILLIAMS,.OFMASSILLON, OHIO, AND JOSEPH W. MCHUGH, OF PITTSBURGH, PENNSYLVANIA,ASSIGNORS TO PTTSBU'RGH STEEL FOUNDRY CORPORATION, OF GLASSPORT,PENNSYLVANA, A CORPORATION OF PENNSYLVANIA i I ANNEALING- BOXApplication filed February 10, 1928. Serial No. 253,364.

The invention relates to annealing boxes of the type in which a hoodrests upon a flat surfaced base of rectangular` ferm and of very heavysection provided with a peripherally disposed uprising flange which,with the lower edge of the hood, forms a trough in which sand is packedto prevent ingress of air during the annealing operation. These boxesare subjected to very high temperatures, and the corners of the baseplate, being heavy and unsupported, sag sufficiently under the heatingto break 'the sand seal, permitting air to reach the hot materialsinside of the hood. This sagging of the corners not only breaks the sandseal, but drags on the floor when taking the box out of an oven. V

The object of the invention is to provide a base for such an annealingbox in which the tendency of the corners to sag is substantiallyeliminated, and which requires less metal in its construction than priorThe invention resides in the provision of an.

annealing boX base plate having its corners of reduced section fordecreasing the weightof unsupported metal at those points and thus`substantially eliminate sagging and consequent ingress of air duringthe heating. Preferably this is accomplished by providing a base havingcorners biased from the normally substantially rectangular outline ofthe base.

In the accompanying drawings, which illustrate the preferred embodimentof the invention, Fig. 1 is a plan view of the iinproved base with ahood set thereon; Fig. 2 a longitudinal sectional view taken on lineIL-II, Fig. 1; Fig. 3 a transverse sectional View taken on line III-IH,Fig. l, the hood not being shown in Figs. 2 and 3 for simplicity ofrepresentation; and l a detail setional view taken on the line lV-V,Fig. l.

Referring to these figures, the structure shown comprises amaterial-supporting base l of fundamentally rectangular outline,provided peripherally with a vertical flange 2. On its under sideparallel grooved roller tracks 3 and 4c are provided, together withspaced reinforcing webs or ribs 5, and at its ends there are couplinglugs 6 for attachment to a means of moving the box. A cover or hood 7,of the substantially rectangular form commonly used, rests on the uppersurface of the base l inside the flange 2, the space between the hoodand the flange being `filled with a packing material, such as sand, toseal the interior of the hood against the ingress of air during anannealing operation.

The baseis fundamentally rectangular, but according to the invention itscorners are biased in a manner similar to that shown in Fig. l. Thisbiasing or cutting back ofthe corners is carried inwardly to bring thesurfaces of the flange on the biased corner as near to the corners ofthe hood as is consistent with adequate sealing.

In the use of annealing bones and hoods the sides and ends of the lattergenerally buckle considerably, so that provision is made for a troughbetween the hood and the base flange which is wide enough to allow suchdistortion without consequent breaking of the seal. The

meeting of the sides and ends, however, has a reinforcing effect uponthe corners, so that they do not buckle appreciably, and for this reasonthe biased corners may be outback to forma narrower trough than is usedat the sides and ends.` i c The effect of this cutting off the cornersis to materially decrease the amount of unsupported metal at thosepoints, so that there is little, if any, tendency for the corners to sagunder heat, and a perfect seal can be maintained during the annealingoperation. The corners may be biased to truncate the corner angle toform a single plane connecting the tivo adjacent sides; or they may bearcuate. The somewhat arcuate corner 8 shown in Fig. 1 is preferredbecause when thus biased the corner is brought closer to the hood thanby making it truncate asdefined above, and the unsupported metal at thecorner is thus re duced to a minimum. In order to further reduce theweight at the corners of the base, the thickness of the cerner sectionmay be reduced, as shown in Fig. 4, where the section of the bottom l atthe corner decreases outwardly, being a minimum at the outermost corner.

By the use of this form of annealing box base, all danger of distortionsufficient to disturb the seal is eliminated. 'The base can be made aseasily as the forms hitherto used, and because less metal is required,the bases are cheaper, are easier to move, andless heat is requiredin`bringing the box and its contents up to annealingtemperature. y

According to the provisions of the patent statutes We have explained theprinciple and operation of our invention, and have illustratedanddescribed what We new consider to be its best embodiment. However, Wedesire to have it understood that7 Within the scope of the appendedclaims, the invention inay be practiced otherwise than as specificallyillustrated and described.

lVe claim:

l. An annealing box comprising` a bottom olY substantially rectangularoutline provi-ded at its edges with a. peripheral upwardly extending`flange, and a hood adapted to rest on said bottoinand to torni with saidflangea trough for a sealing medium, the corners of said'bottoinbeingbiased'to bring said flange closer to the hood at thev corners thanalong` the sides and thus to reduce the amount of unsupported :metal atthe corners and to clinii'nate the breaking of a seal by the sagging ofcorners When the box is in service.

2. Anannealing bon comprising a base of substantially rectangularoutline provided at its edges with a peripheral upwardly extending`'flan-ge, and a hood adapted to rest on said Ibase and to 4torni withsaid iangre a trough for a sealinginedluin, the corners of the basebeing reduced in section outwardly from adjacent `the corners oi thehood to eliminate breaking et a seal by the sagging 0l corners when thebox is in service.

3. An annealing box comprising a base oi substantially rectangularoutline provided at its edges with a peripheral upvvardlyextendingiange, and a hood adapted to rest on said base and to form with saidflange a trough for a sealing medium, the corners of said base being,rybiased to bring said flange closer to the corners of the hood ythan atthe sides and being also of reduced section out Wardly 'from adjacentthe corners of the hood to reduce the ainount of unsupported metal atthe corners and to eliminate the breaking' of a seal by the sagging ofcorners ,When the box is in service.

In testimony whereof, We hereunto sign our naines.

HARVEY VHJLAMS. JOSEPH W. MOHUCYH..

